This invention relates to devices used in a blood vessel or other lumen in a patient""s body. In particular, this invention relates to distal protection devices having a guidewire which can be controlled independently of a functional element such as a filter which is carried by the guidewire.
During vascular surgery or endovascular treatment of vessels including atherectomy, balloon angioplasty, and/or stent deployment, debris such as plaque and blood clots can move from the treatment site through a vein or artery, thus compromising the flow of blood at a location distal from the treatment site. Various distal protection systems have been developed to prevent such debris from embolizing in the vessel. Such distal protection devices include filters and occlusive devices, (e.g., balloons) placed distally of the treatment site.
It is desirable to place a distal protection device at a chosen location in order to achieve good sealing between the device and the wall of the vessel. Frequently it is necessary to match the protection device diameter with the vessel diameter, and vessels are known to taper or to have diameters that vary due to disease. It is also desirable to place the protection device in a relatively disease free portion of the vessel so as to minimize liberation of emboli from the wall of the vessel due to interaction with the protection device. Further, it is desirable that the device remains at the desired location during the procedure. Excessive motion of the wire or elongate guide member used to deliver the device can advance a protection device distally, beyond branch vessels, which thereby become unprotected from emboli.
Distal protection devices typically are mounted on a wire or tube that functions as a guidewire. As used herein the term guidewire means either a traditional guidewire or other elongate member or hollow tube that is used in delivering the distal protection device. The protection device can be either a filter or an occlusive device such as a balloon. The distal protection devices are either fixedly attached to the guidewire or attached so as to permit a limited amount of motion between the device and the guidewire. Frequently, the same guidewire used to carry the device is also used to guide various catheters to and from the treatment site. For example, during the procedure, catheters may be exchanged over this guidewire. When catheters are exchanged inadvertent wire movement can cause the protection device to move within the vessel. Excessive wire motion can also retract a protection device proximally, where it can potentially become entangled in a stent or even be inadvertently removed from the vessel being protected. In some vessels, when guide catheters are repositioned, the protection device also tends to move within the vessel. This is undesirable because captured emboli can be released and/or new emboli can be formed distal to the protection device, blood vessels can be damaged, and/or the device can entangle with an implant such as a stent. Therefore, it is clear that too much movement of the device within the vessel could have catastrophic results.
Some work already has been done to provide for limiting the movement of a distal protection device or distal filter with respect to a guidewire. For example, a guidewire having a distal stop is described in WO 01/35857 (Tsugita et al.). The filter slides on the guidewire but cannot slide off the wire due to the distal stop. Another device which includes a slideable vascular filter having both distal and proximal sliding elements that move independently of each other over a mandrel is described in WO 01/21100 (Kusleika et al.) and is illustrated in FIG. 37. The device includes filter F, distal and proximal sliding elements (D and P) at either end of the filter, and stop S, all disposed about mandrel M. Body B of the filter F assumes a generally tubular shape and is made of a resilient material. The proximal length of the filter body has opening O therein. This opening permits body fluid with particulate therein to enter the enclosure formed by body B of the filter. The mandrel is sufficiently flexible so that the device can be deployed in a curving body passageway. The distal-most length of the mandrel is shown having a flexible helically wound coil T thereover. This coil enhances the flexibility of the distal tip. The stop is at a fixed position on the mandrel and thus limits the movement of the sliding elements D and P. The filter is thus allowed to move along the mandrel or guidewire only the distance to the stop. While this system meets many of the needs in the art, it limits the range of motion of the filtration device on the guidewire, and the precision with which it can be placed is limited.
Another known limitation of distal protection devices relates to wire bias. It is well known that a guidewire will conform to the outside of a curved vessel on advancement of the wire in a distal direction and will conform to the interior of a curved vessel during retraction of the wire. Most distal protection devices are attached to wires, and when they are deployed in vessel curvature the wire bias will alternately move the device between the inside and the outside of the vessel curve. For filters this can defeat the protection effect by compressing the filter opening. For occlusion devices the wire bias effect can cause excessive motion of the occlusion device with potential liberation of embolic debris from the vicinity of the occlusive element.
Some work already has been done to provide for limiting the radial movement of a guidewire relative to a distal protection device. For example, a protection device having a proximal loop is described in EP 1,181,900 A2, (U.S. Ser. No. 09/628,212, Oslund et al.). A loop is provided proximal to the filter to immobilize the wire against the vessel wall regardless of wire bias. While this system meets many of the needs in the art, it adds bulk to the device and thereby limits crossing profile.
It would be desirable to have a distal protection system that can be precisely placed at a location within the vasculature and that can accommodate a wide range of axial and radial wire motion without disturbing the device""s position.
This invention is a distal protection device for use in a body lumen. The device includes a guidewire system which may include separate individual guidewire or elongate members. A functional element, such as a filter or occlusive device including a balloon is mounted on the guidewire system. The device is able to filter or occlude debris and blood clots in a body lumen and/or prevents them from moving distally and causing emboli. The various embodiments of the invention disclosed herein allow the user to accurately place the filter in the vessel and permit substantial guidewire movement during the filter use without dislodging the filter. Motion of the guidewire can be independent of the motion of the distal protection device and the contact force between the guidewire and the protection device can be cushioned in the device of this invention. In addition, in some of the embodiments disclosed herein the user of the device is able to enable or disable the relative motion feature between the guidewire and the protection device and/or to obtain tactile feedback to indicate the limit of the range of guidewire movement when the relative motion feature is enabled.
In a first embodiment, this invention is a distal protection device for use in a body lumen comprising first and second elongate members having distal and proximal ends, a functional element carried by the second elongate member, the functional element being expandable from a delivery configuration to an expanded deployed configuration when the functional element is deployed in the body lumen; and means for moveably connecting the first and second elongate members over a range of motion from a first relative position to a second relative position such that when the functional element is deployed in the lumen the first elongate member may be moved without resulting in corresponding movement of the functional element, the distal end of the second elongate member being distal to the distal end of the first elongate member over the entire range of motion.
The connecting means may comprise a flexible tether. The connecting means may comprise a distal portion of the first elongate member having a lumen which is configured to slideably receive a proximal portion of the second elongate member, the second elongate member having an enlarged proximal end, the lumen of the distal portion having a constricted portion defining an opening which is smaller than the enlarged proximal end of the second elongate member such that the second elongate member is slideably retained in the lumen of the distal portion. The connection means may comprise a telescoping connector between the first and second elongate members. The connecting means may comprise a sleeve having at least one lumen sized to slideably accommodate the first and second elongate members, the distal end of the first elongate member having a stop positioned distal to the at least one lumen and sized to prevent the distal end of the first elongate member from being withdrawn from the at least one lumen, the second elongate member having a stop positioned proximal to the at least one lumen and sized to prevent the proximal end of the second elongate member from being withdrawn from the at least one lumen. The functional element may comprise a filter, and the filter may have a body defining a proximally facing opening when in the expanded deployed configuration. The functional element may comprise an inflatable balloon or a body defining an interior cavity. A sleeve may be contained within the interior cavity. The connecting means also may comprise a first eyelet at the distal end of the first elongate member and a second eyelet at the proximal end of the second elongate member, the first eyelet forming a first loop which encircles the second elongate member and the second eyelet forming a second loop which encircles the first elongate member.
The functional element may include a proximal end connected to the second elongate member and a distal end connected to a distal slider which is slideable over the second elongate member, and further may include a loop at the distal end of the first elongate member which encircles the second elongate member between the proximal end of the functional element and the distal slider. The loop may be contained within the interior cavity. The connecting means may comprise the first elongate member having a tubular body having a lumen with an interior diameter and the second elongate member having a first region with an exterior diameter less than the interior diameter of the lumen of the tubular body, the first region being slideably received in the lumen of the tubular body. The second elongate member may have enlarged portions adjacent proximal and distal ends of the first region, which have an exterior diameter larger than the interior diameter of the lumen of the tubular body. At the first relative position, a first surface of the first elongate member can abut against a first surface of the second elongate member. This may further include means for gradually increasing resistance to movement between the first elongate member and the second elongate member as the first surface of the first elongate member is moved toward the first surface of the second elongate member.
The device may further comprise means for moveably connecting the filter and the first elongate member over a range of motion from a first position when the connecting means is in a relaxed state to a second position when the connecting means is in an expanded state such that resistance to movement between the filter and the first elongate member increases over the range of motion as the second position is approached. There also may be a means for locking the first elongate member to the second elongate member, the locking means having a locked position where the relative positions of the first and second elongate members are locked and an unlocked position where the first elongate member can be moved over the range of motion from the first relative position to the second relative position without resulting in movement of the second elongate member.
In a second embodiment, this invention is a distal protection device for use in a body lumen comprising a first elongate member having distal and proximal ends, a distal portion of the first elongate member having a lumen; a second elongate member having a distal end and an enlarged proximal end, the lumen of the distal portion of the first elongate member being sized to slideably receive a proximal portion of the second elongate member and having a constricted portion defining an opening which is smaller than the enlarged proximal end of the second elongate member such that the second elongate member is slideably retained in the lumen of the first elongate member; and a functional element carried by the second elongate element, the functional element being expandable from a delivery configuration to an expanded deployed configuration when the functional element is deployed in the body lumen.
In a third embodiment, this invention is a distal protection device for use in a body lumen comprising a first elongate member having distal and proximal ends; a second elongate member having distal and proximal ends; a functional element carried by the second elongate element, the functional element being expandable from a delivery configuration to an expanded deployed configuration when the functional element is deployed in the body lumen; and a sleeve having at least one lumen sized to slideably accommodate the first and second elongate members, the distal end of the first elongate member having a stop positioned distal to the at least one lumen and sized to prevent the distal end of the first elongate member from being withdrawn proximally from the at least one lumen, the second elongate member having a stop positioned proximal to the at least one lumen and sized to prevent the proximal end of the second elongate member from being withdrawn distally from the at least one lumen.
In a fourth embodiment, this invention is a distal protection device for use in a body lumen comprising a first elongate member having distal and proximal ends; a second elongate member having distal and proximal ends; a functional element carried by the second elongate element, the functional element being expandable from a delivery configuration to an expanded deployed configuration when the functional element is deployed in the body lumen; and a first eyelet at the distal end of the first elongate member and a second eyelet at the proximal end of the second elongate member, the first eyelet forming a first loop which encircles the second elongate member and the second eyelet forming a second loop which encircles the first elongate member.
In a fifth embodiment, this invention is a distal protection device for use in a body lumen comprising a first elongate member having distal and proximal ends; a second elongate member having distal and proximal ends; a functional element carried by the second elongate element, the functional element being expandable from a delivery configuration to an expanded deployed configuration when the functional element is deployed in the body lumen, the functional element having a proximal end which is connected to the second elongate member and a distal end connected to a distal slider which is slideable over the second elongate member; and a loop positioned at the distal end of the first elongate member which encircles the second elongate member between the proximal end of the functional element and the distal slider.
In a sixth embodiment, this invention is a distal protection device for use in a body lumen comprising a first elongate member having distal and proximal ends and having a tubular body having a lumen with an exterior diameter; a second elongate member having distal and proximal ends and having a first region with an exterior diameter less that the interior diameter of the lumen of the tubular body, the first region being slideably received in the lumen of the tubular body; and a functional element carried by the second elongate element, te functional element being expandable from a delivery configuration to an expanded deployed configuration when the functional element is deployed in the body lumen.
In a seventh embodiment, this invention is a method of occluding blood flow through the lumen of a vessel during a percutaneous procedure performed with a treatment device at a treatment site in the vessel comprising providing a distal protection device including a guidewire having first and second elongate members and an occlusive device carried by the second elongate member, the occlusive device being expandable from a delivery configuration to a deployed configuration, the first elongate member being connected to the second elongate member in a manner that permits the first elongate member to be moved with respect to the second elongate member over a range of motion without moving the second elongate member; introducing the guidewire and the occlusive device in its delivery configuration into the lumen of the vessel; advancing the guidewire through the vessel until the occlusive device is positioned at a desired location distal to the treatment site, at least a proximal portion of the first elongate member extending outside of the vessel; expanding the occlusive device to its deployed configuration to occlude the lumen of te vessel; advancing the treatment device over the guidewire to the treatment site while holding the first elongate member; and performing the percutaneous procedure at the treatment site with the treatment device while the lumen of the vessel is occluded.
In an eighth embodiment, this invention is a distal protection device for use in a body lumen comprising an elongate member having distal and proximal ends and having at least one longitudinal groove having distal and proximal ends; and a functional element carried by the elongate member, the functional element being expandable from a delivery configuration to an expanded deployed configuration when the functional element is deployed in the body lumen, the functional element having at least one projection sized to be accommodated within the groove and configured to be slideable within the groove between the distal and proximal ends of the groove.
In a ninth embodiment, this invention is a method of making a guidewire system for delivery of a functional element to a desired location in a body lumen comprising providing a first elongate member, a second elongate member and a functional element; mounting the functional element on the second elongate member; and connecting the first elongate member to the second elongate member in a manner that permits the first elongate member to be moved with respect to the second elongate member without moving the second elongate member.
In a tenth embodiment, this invention is a method of filtering emboli from blood flowing through the lumen of a vessel during a percutaneous procedure performed with a treatment device at a treatment site in the vessel comprising providing a distal protection device including a guidewire having first and second elongate members and a filter carried by the second elongate member, the filter being expandable from a delivery configuration when the filter is restrained to an expanded deployed configuration when the filter is unrestrained, the first elongate member being connected to the second elongate member in a manner that permits the first elongate member to be moved with respect to the second elongate member over a range of motion without moving the second elongate member; introducing the guidewire and filter in its delivery configuration into the lumen of the vessel; advancing the guidewire through the vessel until the filter is positioned at a desired location distal to the treatment site, at least a proximal portion of the first elongate member extending outside of the vessel; removing the restraint on the filter to expand the filter within the lumen of the vessel to its expanded deployed configuration; advancing the treatment device over the guidewire to the treatment site while holding the first elongate member; performing the percutaneous procedure at the treatment site with the treatment device; and filtering emboli from blood during the percutaneous procedure with the filter.
In a eleventh embodiment, this invention is a distal protection device for use in a body lumen comprising an elongate member having distal and proximal ends and at least one stop spaced proximally of the distal end; a functional element having a first slider disposed for translation along the elongate member between the stop and proximal end, the stop limiting translation of the slider in a distal direction; and means for gradually increasing the resistance between the slider and stop as the stop is moved proximally toward the slider.
The functional element may comprise a second slider disposed for translation along the elongate member between the stop and distal end, the stop limiting translation of the second slider in a proximal direction and wherein the means for increasing resistance includes means for gradually increasing the resistance between the second slider and the stop as the stop is moved distally toward the second slider. The means for increasing resistance may include a spring, an elastomeric tube, or first and second magnets having like-magnetic facing poles.
In an twelfth embodiment, this invention is a distal protection device for use in a body lumen comprising a first elongate member having distal and proximal ends; a second elongate member having distal and proximal ends; a functional element carried by the second elongate element, the functional element being expandable from a delivery configuration to an expanded deployed configuration when the functional element is deployed in the body lumen; and means for moveably connecting the filter and the first elongate member over a range of motion from a first relative position when the connecting means is in a relaxed state to a second relative position when the connecting means is in an expanded state such that resistance to movement between the filter and the first elongate member increases over the range of motion as the second relative position is approached.
In a thirteenth embodiment, this invention is a distal protection device for use in a body lumen comprising a first elongate member having distal and proximal ends; a second elongate member having distal and proximal ends; a functional element carried by the second elongate element, the functional element being expandable from a delivery configuration to an expanded deployed configuration when the functional element is deployed in the body lumen; and means for locking the first elongate member to the second elongate member, the locking means having a locked position where the relative positions of the first and second elongate members are locked and an unlocked position where the first elongate member can be moved over a range of motion from a first relative position to a second relative position without resulting in movement of the second elongate member.
In a fourteenth embodiment, this invention is a method of filtering emboli from blood flowing through the lumen of a vessel during a percutaneous procedure performed with a treatment device at a treatment site in the vessel comprising providing a distal protection device including a guidewire having first and second elongate members and a filter carried by the second elongate member, the filter being expandable from a delivery configuration when the filter is restrained to an expanded deployed configuration when the filter is unrestrained; locking the first elongate member to the second elongate member so that their relative positions are fixed; introducing the guidewire and filter in its delivery configuration into the lumen of the vessel; advancing the guidewire through the vessel until the filter is positioned at a desired location distal to the treatment site; removing the restraint on the filter to expand the filter within the lumen of the vessel to its expanded deployed configuration; unlocking the first elongate member from the second elongate member so that the first elongate member is moveable with respect to the second elongate member over a range of motion from a first relative position to a second relative position without resulting in movement of the second elongate member; advancing the treatment device over the guidewire to the treatment site after the first elongate member has been unlocked from the second elongate member; performing the percutaneous procedure at the treatment site with the treatment device; and filtering emboli from blood during the percutaneous procedure with the filter.
In a fifteenth embodiment, this invention is a method of occluding blood flow through the lumen of a vessel during a percutaneous procedure performed with a treatment device at a treatment site in the vessel comprising providing a distal protection device including a guidewire having first and second elongate members and an occlusive device carried by the second elongate member, the occlusive device being expandable from a delivery configuration to an expanded deployed configuration; locking the first elongate member to the second elongate member so that their relative positions are fixed; introducing the guidewire and occlusive device in its delivery configuration into the lumen of the vessel; advancing the guidewire through the vessel until the occlusive device is positioned at a desired location distal to the treatment site; expanding the occlusive device to its expanded deployed configuration to occlude the lumen of the vessel; unlocking the first elongate member from the second elongate member so that the first elongate member is moveable with respect to the second elongate member over a range of motion from a first relative position to a second relative position without resulting in movement of the second elongate member; advancing the treatment device over the guidewire to the treatment site after the first elongate member has been unlocked from the second elongate member; and performing the percutaneous procedure at the treatment site with the treatment device while the lumen of the vessel is occluded.